Clay-coated record material of improved image durability

A pressure sensitive record system having improved resistance to fading comprising a manifold set of at least one transfer sheet and at least one receiving sheet, said transfer sheet carrying on at least a portion of the surface thereof in an insulated pressure-releasable state a solution of image-forming material consisting essentially of an electron-donating organic dye precursor adapted to produce color on contact with an electron-acceptor solid, and said receiving sheet carrying on at least a corresponding8c area of an adjacent surface a uniform even distribution of a multitude of finely divided particles of a clay consisting essentially of at least about 15% by weight of montmorillonite clay mineral having an expanding three-layer lattice molecular structure exhibiting when analyzed in the presence of benzyl ether of Michler's hydrol by X-ray diffraction at least a discernible peak at a 2 .theta. value of 5.6-5.7, a sufficient proportion of said molecular structure having been irreversibly chemically altered to impart substantially Newtonian viscosity behavior to an aqueous suspension containing at least about 15% by weight of said clay particles.

A pressure-sensitive self-contained image-producing record material having improved resistance to fading comprising a sheet support having on one side thereof finely divided liquid inclusions of a solution of an organic dye precursor maintained in an isolated pressure-releasable condition, said precursor consisting essentially of an electron-donating compound adapted to produce color on contact with an electron-acceptor solid, and on the same side of said support a uniform even distribution of a multitude of finely divided particles of a clay consisting essentially of at least about 15% by weight of montmorillonite clay mineral having an expanding three-layer lattice molecular structure exhibiting when analyzed in the presence of benzyl ether of Michler's hydrol by X-ray diffraction at least a discernible peak at a 2 .theta. value of 5.6-5.7, a sufficient proportion of said molecular structure having been irreversibly chemically altered to impart substantially Newtonian viscosity behavior to an aqueous suspension containing at least about 15% by weight of said clay particles.

A method of forming a colored image of improved resistance to fading on a record material comprising a support carrying a uniform even distribution throughout a recording area thereof of a multitude of finely divided particles of a clay consisting essentially of at least about 15% by weight of montmorillonite clay mineral having an expanding three-layer lattice molecular structure exhibiting when analyzed in the presence of benzyl ether of Michler's hydrol by X-ray diffraction at least a discernible peak at a 2 .theta. value of 5.6-5.7, a sufficient proportion of said molecular structure having been irreversibly chemically altered to impart substantially Newtonian viscosity behavior to an aqueous suspension containing at least about 15% by weight of said clay particles, which comprises the step of imagewise contacting said material with an image-forming solution consisting essentially of an electron-donating colorless dye precursor compound.